ServletContextAttributeListener (Jakarta EE Web Profile API)

All Superinterfaces:

EventListener
```
public interface ServletContextAttributeListener
extends EventListener
```
Interface for receiving notification events about ServletContext attribute changes.
In order to receive these notification events, the implementation class must be either declared in the deployment descriptor of the web application, annotated with WebListener, or registered via one of the addListener methods defined on ServletContext.
The order in which implementations of this interface are invoked is unspecified.

Since:

Servlet 2.3

See Also:

ServletContextAttributeEvent

Method Summary

All Methods Instance Methods Default Methods
Modifier and Type	Method	Description
`default void`	`attributeAdded(ServletContextAttributeEvent event)`	Receives notification that an attribute has been added to the ServletContext.
`default void`	`attributeRemoved(ServletContextAttributeEvent event)`	Receives notification that an attribute has been removed from the ServletContext.
`default void`	`attributeReplaced(ServletContextAttributeEvent event)`	Receives notification that an attribute has been replaced in the ServletContext.

- Method Detail
  - attributeAdded
```
default void attributeAdded(ServletContextAttributeEvent event)
```
    Receives notification that an attribute has been added to the ServletContext.
    
    Parameters:
    
    event - the ServletContextAttributeEvent containing the ServletContext to which the attribute was added, along with the attribute name and value
  - attributeRemoved
```
default void attributeRemoved(ServletContextAttributeEvent event)
```
    Receives notification that an attribute has been removed from the ServletContext.
    
    Parameters:
    
    event - the ServletContextAttributeEvent containing the ServletContext from which the attribute was removed, along with the attribute name and value
  - attributeReplaced
```
default void attributeReplaced(ServletContextAttributeEvent event)
```
    Receives notification that an attribute has been replaced in the ServletContext.
    
    Parameters:
    
    event - the ServletContextAttributeEvent containing the ServletContext in which the attribute was replaced, along with the attribute name and its old value